1. Field of the Invention
This invention relates generally to blocks used for the construction of retaining walls. More specifically, the invention relates to a cementitious block that is easier to place into a secure block retaining wall than existing blocks while also being able to be offer alternative methods for increasing the retaining strength of the wall made from the blocks.
2. Description of Related Art
Retaining walls made from dry stacked concrete blocks have become widely accepted for both landscaping and construction projects. These concrete blocks are mass produced, which makes them relatively inexpensive, and are available in several colors and textures. These blocks offer the durability of concrete with the attractiveness of various architectural features. Due to their significant weight, when the blocks are assembled to form a wall, they have the ability to retain soil and earth while aesthetically defining walkways, property lines, and other landscaping features. It is possible to build a wall from such blocks quickly and without the need for special skilled labor, and how quickly the wall is constructed depends on the size of the blocks used and ease of stacking the blocks for the workers.
To increase the structural integrity of the wall made from these blocks, various methods have been introduced to provide features on the blocks to interlock them together. Furthermore, walls formed from blocks that have been interlocked look more professional as the blocks are uniformly and consistently arranged. One example of an interlocking feature is a lip or protrusion extending along the lower rear edge of each block. As each successive course is laid over an underlying course, the lips of the blocks in the new course are fitted over the rear upper edge of the underlying course of blocks, which interlocks the blocks and also sets the new course back from the lower course it is resting on a predetermined distance. Another interlocking method is the use of pins extending vertically between courses of blocks to resist lateral shifting or movement between adjacent blocks and courses. Similar to the lip discussed above, pins also provide a registry function, by assuring that the front faces of the blocks are vertically aligned or setback a predetermined distance.
As the use of these concrete retaining wall blocks becomes prevalent in commercial and large-scale projects, additional soil-reinforcing materials and methods are needed to ensure that the retaining wall can prevent lateral displacement of the soil and toppling of the wall. One material that is used is a geogrid, which are commonly used to reinforce retaining walls by preventing the soils from moving by transferring the forces to a larger area of soil other than just the soil in contact with the wall. Alternatively, soil anchors or metal ribbed or wave-shaped strips can be attached to the wall and then buried in the backfilled area to provide additional strength to the retaining wall. Additionally, several of these larger commercial projects have specifications requiring engineered backfill rather than just retaining the native soil to ensure the wall maintains its integrity.
It is therefore desirable to have relatively lightweight block that allows easier and quicker installation while allowing the use of various soil-reinforcing methods and materials with increased room for more engineered backfill in contact with the individual blocks of the wall.